In which form of impetigo is Staphylococcus aureus the sole causative agent?

Bullous impetigo is primarily associated with Staphylococcus aureus as the sole causative agent. This form of impetigo presents with larger, fluid-filled blisters that can easily rupture, leading to the formation of a characteristic thick, honey-colored crust. The presence of the exfoliative toxin produced by Staphylococcus aureus contributes to the formation of these bullae, distinguishing it from non-bullous impetigo, which is more commonly caused by Streptococcus pyogenes and may involve both streptococcal and staphylococcal infections but not exclusively Staphylococcus aureus.

In the case of non-bullous impetigo, Staphylococcus aureus may be found, but it often occurs alongside Streptococcus pyogenes, making it less specific for a single causative organism. Understanding the specific microbial causes of each form of impetigo is essential for appropriate management and treatment.